A longtime aide to City Comptroller John Liu admitted in court last week that she conspired to commit financial fraud to help Liu’s mayoral campaign.

“I didn’t realize how bad it was,” said Sharon Lee, as she incriminated herself on the stand.

Most bosses would fire a dishonest employee, but not Liu. The proud boss told The Wall Street Journal: “I have full confidence in her ability.”

Well, her ability isn’t in doubt.

Her honesty is what’s in question — and according to her testimony, it’s up for sale.

Lee said she had asked family and friends to make campaign contributions for which she would then reimburse them. It’s illegal to hide the true source of donations that way, but the setup seems to be a pattern for those closest to Liu, a man who is supposed to be the city’s fiscal watchdog.

Indeed, Lee was testifying in the trial of two Liu associates, including his former campaign treasurer, who allegedly created networks of “straw donors” to steal from the city’s matching-funds program.

The more we hear in court, the more Liu’s office sounds like something out of Charles Dickens’ “Oliver Twist,” where the pupils in Fagin’s workshop bring him back their ill-gotten gains.

But ever the artful dodger, Liu has thus far avoided any charges himself.